XSS in Opnsense
CVE-2019-25371
OPNsense 19.1 contains a reflected cross-site scripting vulnerability that allows unauthenticated attackers to inject malicious scripts by exploiting insufficient input validation in the host parameter. Attackers can submit crafted POST requests to the diag_ping.php endpoint with script payloads in the host parameter to execute arbitrary JavaScript in users' browsers.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.003 (14.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 15th percentile — 14.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.000
Affected products
- Opnsense — versions 19.1
Weakness classification (CWE)
References
- www.exploit-db.com/exploits/46351 (Exploit, VDB Entry, Third Party Advisory, exploit)
- opnsense.org (Product, product)
- forum.opnsense.org/index.php (Release Notes, patch)
- www.vulncheck.com/advisories/opnsense-reflected-xss-via-diagpingphp (Broken Link, third-party-advisory)
Frequently asked questions
- What is CVE-2019-25371?
- CVE-2019-25371 is a medium-severity vulnerability in Opnsense, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-02-15.
- How severe is CVE-2019-25371?
- Medium severity. CVSS v3 base score is 6.1 out of 10.